#include "Rational.h"
#include <sstream> // Used in toString to convert numbers to strings
#include <cstdlib> // For the abs function
Rational::Rational()
{
  numerator = 0;
  denominator = 1;
}

Rational::Rational(int numerator, int denominator)
{
  int factor = gcd(numerator, denominator);
  this->numerator = ((denominator > 0) ? 1 : -1) * numerator / factor;
  this->denominator = abs(denominator) / factor;
}

int Rational::getNumerator() const
{
  return numerator;
}

int Rational::getDenominator() const
{
  return denominator;
}

// Find GCD of two numbers 
int Rational::gcd(int n, int d) 
{
  int n1 = abs(n);
  int n2 = abs(d);
  int gcd = 1;

  for (int k = 1; k <= n1 && k <= n2; k++)
  {
    if (n1 % k == 0 && n2 % k == 0)
      gcd = k;
  }

  return gcd;
}

Rational Rational::add(const Rational& secondRational) const
{
  int n = numerator * secondRational.getDenominator() +
    denominator * secondRational.getNumerator();
  int d = denominator * secondRational.getDenominator();
  return Rational(n, d);
}

Rational Rational::subtract(const Rational& secondRational) const
{
  int n = numerator * secondRational.getDenominator()
    - denominator * secondRational.getNumerator();
  int d = denominator * secondRational.getDenominator();
  return Rational(n, d);
}

Rational Rational::multiply(const Rational& secondRational) const
{
  int n = numerator * secondRational.getNumerator();
  int d = denominator * secondRational.getDenominator();
  return Rational(n, d);
}

Rational Rational::divide(const Rational& secondRational) const
{
  int n = numerator * secondRational.getDenominator();
  int d = denominator * secondRational.numerator;
  return Rational(n, d);
}

int Rational::compareTo(const Rational& secondRational) const
{
  Rational temp = subtract(secondRational);
  if (temp.getNumerator() < 0)
    return -1;
  else if (temp.getNumerator() == 0)
    return 0;
  else
    return 1;
}

bool Rational::equals(const Rational& secondRational) const
{
  if (compareTo(secondRational) == 0)
    return true;
  else
    return false;
}

int Rational::intValue() const
{
  return getNumerator() / getDenominator();
}

double Rational::doubleValue() const
{
  return 1.0 * getNumerator() / getDenominator();
}

string Rational::toString() const
{
  if (denominator == 1)
    return to_string(numerator); // See Ch7 for to_string
  else
    return  to_string(numerator) + "/" + to_string(denominator);
}